The key to improvements is to start doing a little more of the things that are a little harder. For example, if your not a good swimmer, then you need to spend a little more time swimming, and less time doing the things you enjoy more, biking and running.
It’s always more enjoyable to do the things we are good at. However, in a sport that is actually a combination of three sports.
For example, if you’re a great biker but your run game is lacking and you aren’t able to hold it strong and are getting passed a lot in the last leg, dial back the biking and pound the pavement a little more. These improvements will be come faster when you’re able to work with a coach.
Focusing on your weakness or weaknesses, may require taking some time away from the other discipline or disciplines, so the best time to do this would be after race season, or prior to your next race season. You will want 6-8 weeks of some focused training to see some improvement in these areas, you will focus on on the skill you are trying to build while maintain the other two disciplines. A good coach will be able to assign workouts to help you work towards your coach, so expect more “key” workouts focus on the sport you’re working to improve.